Spatial light modulators (SLMs) are light modulation devices used in the projector industry. An example of an SLM is a digital micromirror device (DMD). A surface of an SLM includes thousands or hundreds of thousands of picture elements (pixels). With a DMD, the picture elements are mirrors. Light illuminates the mirrors and physical modulation of the mirrors generates the desired image. Projection optics projects the light reflected from the SLM. Using techniques such as color wheels, multiple light sources and modulation of the mirrors, SLM-based projectors can project a full color image. This is referred to as a single modulator or “single chip” projector. However, this type of system can only project one color at a time. Transitions from one color to another can create unwanted artifacts and can cause discomfort in sensitive people. A three modulator (“three chip”) projector uses SLMs dedicated to each projected color, often red, green and blue. This type of projector avoids artifacts cause by color transitions. However, the optics necessary to combine the three images from the three SLMs are large, complex and expensive.